Hard disk drive manufacturing appears to have reached a physical limit of storage density in hard drives that store data using the perpendicular magnetic recording (PMR). In order to continue offering hard drives with increased storage capacities, hard drive manufacturers have begun to introduce hard drives that use storage formats other than PMR, such as shingled magnetic recording (SMR) formats. SMR formats record data by partially overwriting previously recorded data. This allows SMR to offer higher storage capacities than PMR. However, due to the overlapping nature of data stored using SMR, random access write operations usually cannot be performed without risking the destruction of data stored in an adjacent storage location, where overlapping data is stored. To address this, some SMR hard drives organize storage locations into SMR zones. When a random access write operation targets a storage location in an SMR zone, all of the data in the SMR zone can be read, modified according to the write operation, and then written back to SMR zone.